Support arm apparatus

Abstract

A support arm apparatus includes an arm device, a joint device, an extension and retraction device, and an adjustment device. The joint device includes first and second joint seats, and the first joint seat has a receiving space. The extension and retraction device includes a fixed portion and a moving portion that is connected to the fixed portion and that is movable relative to the fixed portion. The adjustment device includes a track seat, a linking seat, and a threaded member. The track seat is inserted fixedly into the receiving space and includes two track walls. The threaded member abuts against support portions of the track walls, and is threadedly engaged with the linking seat.

What is claimed is: 
     
       1. A support arm apparatus comprising:
 an arm device including a first arm and a second arm that cooperates with said first arm to define an elongated passage; 
 a joint device including first and second joint seats that are respectively and pivotally connected to two end portions of said first arm, that are respectively and pivotally connected to two end portions of said second arm, and that cooperate with said first and second arms to form a four-bar linkage, said first joint seat having a receiving space; 
 an extension and retraction device disposed in said passage of said arm device, and including a fixed portion that is pivotally connected to said first arm, and a moving portion that is connected to said fixed portion and that is movable relative to said fixed portion along said passage; and 
 an adjustment device including
 a track seat that is inserted fixedly into said receiving space and that includes two spaced-apart track walls, each of said track walls having a support portion, said support portions of said track walls being spaced apart from each other and defining a gap therebetween, 
 a linking seat that is movably connected to said track seat, said moving portion of said extension and retraction device being co-movably connected to said linking seat, and 
 a threaded member that has a head portion abutting against said support portions of said track walls, and a threaded portion extending through said gap between said support portions of said track walls and threadedly engaged with said linking seat, such that rotation of said threaded member drives movement of said linking seat along said threaded portion of said threaded member and simultaneously drives movement of said moving portion relative to said fixed portion of said extension and retraction device along said passage. 
 
 
     
     
       2. The support arm apparatus as claimed in  claim 1 , wherein:
 said first joint seat includes
 a seat base, 
 two spaced-apart side walls that are connected to said seat base, 
 a back wall that is connected to said side walls, and that cooperates with said seat base and said side walls to define said receiving space, and 
 two stop portions, each of said stop portions being formed between said seat base and a respective one of said side walls; and 
 
 said track walls of said track seat respectively abut against said stop portions of said first joint seat. 
 
     
     
       3. The adjustable support apparatus as claimed in  claim 2 , wherein:
 said track seat has an open end portion disposed outside of said first joint seat, and an opposite end portion extending along a securing axis and inserted fixedly into said receiving space; 
 said back wall of said first joint seat has an engaging stud extending into said receiving space and abutting against said track seat; 
 said track seat further includes a connecting wall interconnecting said track walls and formed with a through hole; and 
 said adjustment device further includes a securing member that extends along the securing axis through said through hole and that engages with said engaging stud of said back wall of said first joint seat for securing said track seat to said first joint seat. 
 
     
     
       4. The support arm apparatus as claimed in  claim 3 , wherein:
 each of said stop portions of said first joint seat has a contact surface elevated from said seat base, and a stop surface being perpendicular to said contact surface; 
 each of said track walls of said track seat has an abutting surface abutting against said contact surface of a respective one of said stop portions; and 
 said connecting wall of said track seat abuts against said blocking surfaces of said stop portions of said first joint seat. 
 
     
     
       5. The support arm apparatus as claimed in  claim 1 , wherein:
 said threaded portion of said threaded member extends along an adjusting axis; 
 said threaded member is formed with a groove; and 
 said adjustment device further includes two pivot members interconnecting said second arm and said second joint seat, and a pivot shaft interconnecting said first arm and said first joint seat, and engaging said groove such that said threaded member is rotatable about the adjusting axis and unmovable along the adjusting axis. 
 
     
     
       6. The support arm apparatus as claimed in  claim 1 , wherein said extension and retraction device includes a cylinder that has an end portion serving as said fixed portion of said extension and retraction device, and a piston rod that is connected telescopically to said cylinder and that has an end serving as said moving portion of said extension and retraction device.